Magnetite Ocean Floor

Magnetic striping of the sea floor after mid ocean ridges and trenches were discovered more evidence was discovered that helped to support the theory that the continents had moved around.

Magnetite ocean floor. The reason tiny grains of magnetite found within the volcanic basalt that make up the ocean floor behave like little magnets. This finding though unexpected was not entirely surprising because it was known that basalt the iron rich volcanic rock making up the ocean floor contains a strongly magnetic mineral magnetite and can locally distort compass readings. These two things were the magnetic striping on the ocean floor and the age of seafloor rocks. Explains how magnetic polarity frozen into seafloor basalts reveals evidence for the creation of new seafloor at mid ocean ridges.

Magnetic stripes and isotopic clocks oceanographic exploration in the 1950s led to a much better understanding of the ocean floor. As magma cools it locks in a recording of the earth s magnetic orientation or polarity at the time of fooling. Among the new findings was the discovery of zebra stripe like magnetic patterns for the rocks of the ocean floor. This distortion was recognized by icelandic mariners as early as the late 18th century.